Machines for lifting and supporting loads, such as forklift trucks or forklifts, have long been known.
For example, in the case of forklifts, those machines are provided with forks, generally vertically mobile such to be able to lower and lift loads at will. In such a manner, it is possible to lower the forks to ground level and drive them under the load and then proceed with lifting and transporting the load to a predetermined place. In other cases, the forks are not only provided with a vertical motion, but are also provided with a horizontal motion that allows a mutual approach and separation between them, such to grasp laterally the objects, adapting to their different shapes and dimensions.
A technical problem that is particularly important concerns the protection of the transported object from scratches and, at the same time, the risk having the object slip from the forks. It is in fact known that the direct contact with metal, material of which the forks are made, determines a low coefficient of friction, mainly in the case of lifting of loads which are also made of metal. Moreover, the direct contact of metal with metal causes scratches, wear and contaminations, therefore damaging the load, at least aesthetically.
In the background art, in order to solve such problem, hand-made solutions are put into practice, which include the occasional application of a covering of cardboard around the fork, fixed through an adhesive tape. This solution, apart from requiring some time for the application and therefore resulting uncomfortable, also produces poor results. In fact, the cardboard does not have mechanical characteristics of resistance, and the same goes for the adhesive tape. Under the action of heavy loads (which can easily exceed hundreds of kilos), the cardboard wears quickly, causing a direct contact between the forks and the load, while at the same the tape peels off unexpectedly, precluding the seal of the cardboard against the forks and therefore causing the easy slipping of the lifted object.
The same problem is also present for loads that are arranged on fixed loading platforms.
In US2006/0197348, a protection device is described for doors of parked cars against the impact.
That device comprises an external resilient material, an intermediate metal layer and magnets for applying the device on the door of the car.
Even if such a device were suitable for application on a fork of a forklift, it is not instead suitable for the same purposes as the present invention.
A resilient material, as described in US2006/0197348, is a material resists impact but is not necessarily suitable to prevent scratching of an object it touches. Further, it does not have an acceptable degree of friction to prevent the slipping of the load moved with the forks of the forklift.
Moreover, in US2006/0197348, two separate and distanced magnetic strips are described, which are positioned at the two opposite sides of the metallic strip. In this manner, when a load is lifted, such a device will bend in its central part where the magnet is not present, such to produce a folding that causes the detachment of the device from the fork.
It is thus evident that the device disclosed in US2006/0197348 is not suitable for the purposes of the present invention, even if it could be applicable on a fork of a forklift.
In U.S. Pat. No. 4,498,697, a similar device is disclosed which is also not suitable for the purposes of the present invention, even if it could be applied on a fork of a forklift.
In this case the device comprises an external tube made of rubber which is internally hollow.
This device, when pressed with a heavy load (more than 1,000 Kg, for example), collapses on itself because it performs like a hollow tube and breaks along the folding line.
Moreover, in U.S. Pat. No. 4,498,697 the device is not rigid enough and, when used on the fork of a forklift, folds and detaches from the fork.